Transmission electron microscopy nucleation

The various latexes were characterized with respect to particle size and size distribution, surface charge and functional group density, and electrophoretic mobility behavior. As observed by transmission electron microscopy all latexes were found highly monodisperse with a uniformity ratio between 1.001 and 1.010, a property due to the short duration of the nucleation period involved in the various radical-initiated heterogeneous polymerization processes. The surface charge density was determined by a colorimetric titration method reported elsewhere [13]. 

Ag2S was also effectively stabilized by cysteinyl ligands. These clusters are synthesized using a molar ratio of 2 1 cysteine silver ions upon which stoichiometric amounts of inorganic sulfide were added to nucleate the nanoparticle, with subsequent size-selective precipitation. The resultant nanoparticles had an absorbance shoulder at 300 nm. Further analysis using high-resolution transmission electron microscopy (HRTEM) revealed a particle size of approximately 9.00 2.25 run in diameter. Selected area electron diffraction (SAED) analysis also demonstrates the highly crystalline natme of the product. ... 

The titania particles precipitate under reaction conditions very similar to those of the silica systems discussed earlier. A critical nucleation concentration of 1.5-3 times [C]eq is measured. This low supersaturation level is not reached until very late in the precipitation reaction (Figure 3). The rate of loss of soluble titania is also independent of the presence of solid surface area. Finally, on the basis of measures of particle surface potentials, nuclei of sizes less than about 20 nm are expected to be unstable and to rapidly aggregate. These results again indicate that during the precipitation of titania, nucleation may occur over much of the reaction period and final particle sizes may be determined by the aggregation of primary particles. These conclusions are supported by the transmission electron microscopy work of Diaz-Gomaz et al. (30). 

L. Chang, Z. Lin, J. Chen, and F. Chen, Transmission electron microscopy study of diamond nucleation on 6H-SiC single erystal with possibility of epitaxy, Appl. 

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